component

SN6505B

Public Made by Adom

by adom

TI low-noise push-pull transformer driver, SOT-23-6. For small isolated DC-DC supplies, up to 1 A switches. Datasheet-verified.

componentpowertransformer-driverisolated-supplypush-pullsot-23-6texas-instruments
Overview Files Discover Packages Releases Dependencies Issues Breadcrumbs Pull Requests Activity

3D Model

Open in new tab ↗
Loads on click. Unloads only if this page sits in the background.

Symbol & Footprint

Schematic Symbol

Open full view ↗
Loads on click. Unloads only if this page sits in the background.

PCB Footprint

Open full view ↗
Loads on click. Unloads only if this page sits in the background.

Datasheet

Open in new tab ↗
Loads on click. Unloads only if this page sits in the background.
Download PDF
Contents

README

markdown

SN6505B

Texas Instruments · Transformer driver · SOT-23-6

Drives the primary of a small center-tapped transformer in push-pull to build an isolated DC-DC supply, the power half of an isolated interface next to a digital isolator. Two integrated switches (D1, D2) alternate at a fixed frequency set on-chip, delivering up to 1 A, and slew-rate control plus spread-spectrum clocking keep EMI low. An EN pin gates it and a CLK pin can synchronize several units. It turns a 5 V rail plus a transformer into an isolated output cleanly.

Pinout

Pin Name Type Function
1 D1 output Open-drain output of the first power MOSFET (1 A, R_ON 0.25 Ω max at 4.5 V). Connects to one outer terminal of the center-tapped transformer primary. Traces should be kept short due to large switching currents.
2 VCC power_in Device supply pin, 2.25 V to 5.5 V. Bypass with a 4.7 µF or greater low-ESR capacitor. Internal UVLO (positive-going 2.25 V, negative-going 1.7 V) turns both outputs off when VCC ≤ 2.25 V.
3 D2 output Open-drain output of the second power MOSFET (1 A, R_ON 0.25 Ω max at 4.5 V). Connects to the other outer terminal of the center-tapped transformer primary. Traces should be kept short due to large switching currents.
4 GND power_in Ground reference; connected to the source of the power MOSFET switches via an internal sense circuit. Must be tied to a low-inductance quality ground plane because large switching currents flow through it.
5 EN input Enable input. Logic high (≥0.7·VCC) enables the device; grounding or leaving floating disables all internal circuitry (I_DIS ≈ 0.1 µA). Tie directly to VCC if unused. Absolute max −0.5 V to VCC + 0.5 V.
6 CLK input External clock input for synchronizing switching (100 kHz to 1600 kHz on SN6505B). Internally pulled down to GND; if no valid clock is detected the device automatically switches to its internal 420 kHz oscillator. Absolute max −0.5 V to VCC + 0.5 V.

Key specifications

Parameter Value
Type Push-pull transformer driver
Switch current 1 A
Switching Fixed frequency (on-chip), spread-spectrum
EMI control Slew-rate limited outputs
Enable EN pin
Sync CLK pin
Supply 2.25-5 V
Package SOT-23-6

Ordering variants

Same part, different packaging or reel option.

  • SN6505BDBVR (SOT-23-6, 420 kHz)
  • SN6505ADBVR (160 kHz)

CAD (KiCad official)

  • Symbol: Power_Management:SN6505BDBV (KiCad official)
  • Footprint: Package_TO_SOT_SMD:SOT-23-6
  • 3D model: SOT-23-6 (KiCad packages3D, STEP)
  • 3D model files: sn6505b-etched.step / sn6505b-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); sn6505b.step / sn6505b.glb are the bare package body.

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

  • Datasheet: Texas Instruments datasheet (43 pp, sha256 dfc57cb042218cb6, retrieved 2026-08-17, tier: manufacturer)
  • Extractor: ds2sf (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
  • CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF